number 1 vs ordinal

number 1 and ordinal both are nouns.

Word	Noun	Adjective	Verb	Adverb
number 1	Yes	No	No	No
ordinal	Yes	Yes	No	No

As nouns, ordinal is a hypernym of number 1; that is, ordinal is a word with a broader meaning than number 1:

Other hypernyms of number 1 include no., ordinal number.

number 1 (noun)	ordinal (noun)
the first element in a countable series	the number designating place in an ordered sequence

number 1 (adjective)	ordinal (adjective)
	being or denoting a numerical order in a series
	of or relating to a taxonomic order